I have a 1991 Ford F150 4x2 with auto trans, it has high mileage and is in desprate need of a rebuild/replace.. My question is what else will I need for this swap? I intend to stay with the same year engine (pull from junk yard then rebuilt or possibly striped and used for a core on a long block). Will all the sensors mount up? will I have to use the "donor truck" wireing harnes. I have helped with engine swaps before, but only on older vehicles (mostaly 70's 4x4 Ford trucks). Will it bolt up to the motor mounts ..... what about the transmision. I do alot of towing and I think going to the bigger motor would be a good choice (am I wrong?). What about gas mileage (I get 12mpg average not towing now)? Sorry for so-many questions...........More information always makes me feel better.